The present disclosure relates generally to electrical machines, and more particularly to thermal management in such electrical machines.
Higher temperatures in electrical machines may be a source of performance degradation, decrease in power density, and reduction in reliability for the electrical machines. Thermal “hot spots” may be a specific manifestation of such an issue. Components of the electrical machines, for example, a stator and a rotor include elements, such as cores, conductors disposed in slots, and/or poles. One or more such elements are generally insulated through insulation layers (e.g., ground wall, phase separators, conductor coating, VPI resin, and the like) to protect them from short circuit. Further, one or more such elements are often among the hottest portions in the electrical machines, due to large ohmic losses. For example, the majority of ohmic losses in the stator component, such as copper losses, are concentrated in stator slots due to generation of heat by winding conductors disposed in the stator slots.
Heat generated due to ohmic losses within the components need to be transmitted through the insulation layers. The extraction of heat from such areas may not be effective due to the poor thermal conductivity of the various insulation layers.
Accordingly, there is a need for an enhanced thermal management in electrical machines.